US4633926A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Heavy duty pneumatic radial tire
Assignee: Bridgestone Corp
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Filing: 1984-12-28
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Granted: 1987-01-06
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Expires: 2004-12-28
Abstract
Abstract Disclosed herein is a heavy duty pneumatic radial tire in which a tread portion of the tire is reinforced by superimposing a belt composed of plural rubberized cord layers upon the outer periphery of a radial structure carcass composed of one or more rubberized cord layers containing cords each arranged in a radial plane of the tire or in a plane deviating at a small angle therefrom; the belt has a substantially lower flexural rigidity at central region than at side regions; and the tread portion has such a tread pattern that has a substantially higher negative ratio at central region than at side regions.
Inventors
- 👤 Akira Tamura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 14:31
CPC Classifications
B; B60; B60C; B60C9/00; B60C9/18; B60C9/20; B60C11/00; B60C11/03; B60C11/0327; B60C11/033; B60C9/28; B60C9/1835; B60C2009/1842; Y; Y10; Y10S; Y10S152/00; Y10S152/902
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
139 words
A heavy duty radial tire comprising; a tread portion, a radial structure carcass composed of one or more rubberized cord layers containing cords each arranged in a radial plane of the tire or in a plane deviating at a small angle therefrom, a belt composed of plural rubberized cord layers upon the outer periphery of the radial carcass and having a substantially lower flexural rigidity at central region than at side regions; wherein the ratio t B /t A in which t A is the maximum thickness of the belt in the central region thereof and t B is the maximum thickness in the side region thereof is 1.25-1.55 and the tread portion has such a tread pattern that a ratio N C /N D in the negative ratio between the central region and the side regions is 1.15-1.50.
Claim 2
Dependent Claim
139 words
A heavy duty radial tire comprising; a tread portion, a radial structure carcass composed of one or more rubberized cord layers containing cords each arranged in a radial plane of the tire or in a plane deviating at a small angle therefrom, a belt composed of plural rubberized cord layers upon the outer periphery of the radial carcass and having a substantially lower flexural rigidity at central region than at side regions; wherein the ratio t B /t A in which t A is the maximum thickness of the belt in the central region thereof and t B is the maximum thickness in the side region thereof is 1.25-1.55 and the tread portion has such a tread pattern that a ratio N C /N D in the negative ratio between the central region and the side regions is 1.15-1.50.
Claim 3
Dependent Claim
21 words
The heavy duty pneumatic radial tire according to claim 1, wherein the ratio of the t B /t A is 1.30-1.45.
Claim 4
Dependent Claim
20 words
The heavy duty pneumatic radial tire according to claim 1, wherein the ratio of N C /N D is 1.25-1.45.
Claim 5
Dependent Claim
21 words
The heavy duty pneumatic radial tire according to claim 1, wherein said tread pattern is a transverse long block lug pattern.
Claim 6
Dependent Claim
45 words
The heavy duty pneumatic radial tire according to claim 1, wherein the thicknesses t A and t B respectively comprise a laminated belt thickness including a covering rubber of the belt cord layers, said covering rubber having an elasticity modulus of 0.35-0.55 kg/mm 2 .
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-01-05 | 1990-07-07 | 1991-01-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-01-05 | 1994-07-07 | 1995-01-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-01-05 | 1998-07-07 | 1999-01-06 | $7700.00 | Window Closed / Lapsed |